Longer distance golf clubs or drivers traditionally had heads made of wood (and were sometimes referred to as “woods”). However, wood, being a natural material, may be subject to unwanted variations or defects, and further requires a great deal of effort and expense to shape properly.
Thus, a new generation of longer distance golf clubs having hollow metal heads (and referred to as “metal woods” or “wood-type” golf clubs) was developed. The use of strong, lightweight metals in the heads has allowed for greater consistency in achieving performance characteristics and more efficient forming techniques.
More recently, metal woods have been formed with a metallic strike face portion and a non-metallic or partially non-metallic aft body portion. By using a hollow aft body portion and by reducing the density of the material used to form the aft body portion, the overall dimensions of the club heads could be increased while maintaining the same head weight. This allowed the heads of metal woods to be designed with increased striking surface area and increased moment of inertia characteristics.
During the game of golf, an individual swings the golf club such that the golf club head travels through a generally arcuate path. Upon impact with a golf ball, a portion of the inertia of golf club, and particularly the inertia of golf club head, is transferred to the golf ball, thereby propelling the golf ball (hopefully) toward an intended target. The position of a center of gravity of the head and the club head's path toward the ball have an influence upon whether the golf ball curves right, curves left, or follows a generally straight route. More specifically, the golf ball follows a generally straight route when the center of gravity is positioned behind the point of engagement of the ball with the striking plate and when the club head is traveling toward the intended target at the moment of impact with the ball. When the center of gravity is offset to one side of the point of engagement and/or when the club is traveling at an angle with respect to the intended path, however, the golf ball may follow a route that curves left or right. Similarly, the offset of the center of gravity of the golf club head above or below (or closer to or farther away from) the point of engagement has an influence upon whether the golf ball exhibits a boring or a climbing trajectory.
The center of gravity (or center of mass) of a golf club head is defined as an equilibrium point, i.e., a point at which the entire weight of the golf club head may be considered as concentrated so that, if supported at that point, the golf club head would remain in static equilibrium in any position.
It has been recognized that changing the position of the center of gravity of the golf club head for different golf clubs may compensate for the swing characteristics of certain golfers so as to correct or modify the route of the golf ball and thereby improve the golfer's game. For example, by moving the center of gravity lower and toward the rear of the golf club head, a golf shot will tend to have an increased loft upon impact between the club and ball. By moving the center of gravity higher and toward the rear of the golf club head, a golf shot will tend to have a decreased loft upon impact (a more “boring” trajectory).
Even more recently, metal woods have been developed whereby the aft body portion may be customized with a plurality of weights strategically placed within or on the aft body portion so as to vary the center of gravity and/or the moments of inertia of the golf club head. Various aft bodies may be pre-manufactured and available for later, final assembly with a specific golf club face. A golfer's swing could be analyzed and the golf club could be, at least partially, customized to account for various imperfections or foibles in the individual golfer's swing styles.
In a customizable club system many different combinations of elements (i.e., shafts, heads, head components, etc.) could be selected and permanently attached to one another to form the ultimate club. However, when buying a golf club, most golfers want to try out the actual, customized club that they will eventually use. To achieve a true feel for the club, the customizable components must be attached to one another as they would be under actual playing conditions. Thus, if a combination of elements is selected and the elements are permanently attached to each other to form the club (as they would be under actual playing conditions, so at to achieve a true feel for the club), but ultimately not chosen by the golfer, this customized and permanently assembled golf club could languish in the shop, possibly never being selected by any golfer. It would be desirable to have a more versatile component assembly system, whereby one could freely attach and then detach the different club elements from one another to try out a variety of club configurations, while at the same time achieving a true feel for the club. This would allow golfers to freely try many different combinations until the best combination for a particular golfer is acheived.
Further, it is possible that an individual golfer's swing style could improve or otherwise vary over time. In such case, a club customized to the golfer's earlier swing style may no longer be appropriate. It is also possible that, after a few initial rounds, the golfer may determine that the customized club does not accommodate his swing as much as would be desired. Even further, new technology or fashions may appear and a golfer may wish to keep current with the latest. A club having detachable elements would allow the golfer to replace the elements and modify or upgrade the club as desired.
It is an object of the present invention to provide a golf club head system that reduces or overcomes some or all of the difficulties inherent in prior known devices. Particular objects and advantages of the invention will be apparent to those skilled in the art, that is, those who are knowledgeable or experienced in this field of technology, in view of the following disclosure of the invention and detailed description of certain preferred embodiments.